The present invention relates to a low foaming alkaline cleaner well suited for cleaning metals. More specifically, the present invention relates to a low foaming cleaner especially well adapted for cleaning steel cans such as black plate cans and tin plated steel cans.
Ferrous-based metals such as steel and tin plated steel are commonly used in making containers such as cans. Such metals generally have a protective oil on the steel surface to protect the surface from abrasion and/or corrosion. Lubricants may also be coated onto the metal surfaces to facilitate forming of the metal into containers. While lubricants are useful in protecting the steel and in facilitating forming operations, the lubricants often must be removed before use is made of the containers. One method and cleaner composition for removal of lubricants is taught in U.S. Pat. No. 4,382,825 which issued May 10, 1983 to McCready. The McCready patent relates to an alkaline cleaner for drawn and ironed black plate steel which includes an alkali metal metasilicate, orthosilicate or combination thereof, optionally an alkali metal carbonate, an alkali metal phosphate, a surfactant such as nonylphenoxy-(polyethoxy) ethanol, and a polyethoxy secondary alcohol. Another example of an alkaline cleaner is that of U.S. Pat. No. 4,349,448 which issued Sept. 14, 1982 to Steele. The Steele patent teaches a low temperature, low foaming alkaline cleaner comprising an alkaline material, an ethoxylated alkyl phenol and an ethoxylated and propoxylated alkyl phenol.
However, there remains a need for improved cleaners. Many metal cleaning operations are conducted on a continuous, line basis and require low foaming, highly efficient cleaners. ALso, cleaners which are employed to clean steel cans such as black plate cans or tin plated steel cans should provide cans which have a pleasing appearance and which are suitable for use, for example, as food containers.
It is an object of the present invention to provide a highly efficient cleaner suitable for both black plate and tin plate surfaces. Further understanding of the present invention will be had from the following disclosure. All percentages and parts herein are by weight unless otherwise indicated.